The Glauconitic Limestone of the area southeast of Esfahan yields a rich Cenomanian cephalopod fauna of Boreal aspect, including species of Anglonautllus, Stomohamites, Sciponoceras, Idiohamites, Ostllngoceras, Mariella, Hypoturrllites, Turrllites, Scaphites, Puzosia, Austiniceras, Hyphoplltes, Schloenbachia, Mantelllceras, Sharpeiceras and Acompsoceras, most of which represent new records for the area. The age of this fauna is unequivocally Lower Cenomanian, and can be correlated in detail at a distance of 5000 km with parts of the northwest European Hypoturrilites carcitanensis and Mantelliceras saxbit Zones. The material studied includes none of the Upper Albian, Middle and Upper Cenomanian elements recorded from the unit by previous workers. The fauna is numerically dominated by acanthoceratids, in marked contrast to the Schloenbachia-dominated faunas of northwestern Europe. This suggests the area lay In the southern parts of the Boreal Realm, where Schloenbachia is known to become progressively scarcer, as Is supported by proximity to the Zagros line marking the juncture of Asian and Arabian plates.